class Solution {
public:
    vector<vector<string>> groupAnagrams(vector<string>& strs) {
         vector<vector<string>> ret;

         unordered_map<string,vector<string>> hash;
         for(auto e:strs)
         {
            string tmp=e;
            sort(tmp.begin(),tmp.end());
            hash[tmp].push_back(e);
         }

         for(auto& [x,y]:hash)
         {
            ret.push_back(y);
         }
         return ret;
    }
};